Apparatus for the reduction of impurities contaminating molten metal



L. JoNgs April 8, 1930.

APPARATUS FOR THE REDUCTION OF IMPURITIES CONTAMINATING MOLIfEN' METALFiled July 13, 1928 ATTORNEY t atented tit, lli 3 J'LLEWELLYN JONES, OFMUNCIE, INDIANA JQLPPAEATUS FOR THE REDUCTION OF IMPURITIESCONTAMINATING MOLTEN METAL Application filed July 19, 1928. Serial No.293,963.

This invention relates to an apparatus for be understood that theinvention is not conthe reduction of impurities in molten metals finedto the disclosure, being susceptible of and is an improvement on theprocess and apsuch changes and modifications as shall doparatusdescribed and claimed in my Patent fine no material departure from thesalient ti #1,4t72,006 dated Uctober 23, 1923. features of the inventionas expressed in the ln carrying out the inventive idea dependappendedclaim. ence is placed in a converter for the reduction In the drawingsof certain impurities by the forcing of air up- Figure 1 is a section ofa vessel in which 1 wardly through a charge of molten metal or thereduction of elements such as oxides, w y resorting 120 in w pressureOver e S gases, and metalloids in the molten metal is face of the metalin side blowing converters. carried out. in this case, which is similarto the furnace Figure 2 is a plan view of a perforated disk melt, themetal ebullates rising from the botnormally disposed in line with theopen end tom to the surface in order to secure contact. of th l, 15 lltis an object of the present invention to Figure 3 is a view in elevationof the outer provide an apparatus for the reduction of esnd of th 11 1 10 t, sential elements in order to improve the qual- Referring moreparticularly to the drawities of metal, by the use of a slag to causethe 'ings, 1O designates an outer metal shell of a elimination ofoxides, gases and metalloids vessel which is interiorly lined with a re-20 from the molten metal obtained from a cupolafractory material 11.-The vessel is open at or furnace, the molten metal being filtered thetop and the bottom is provided witha disthrough molten slag, the slagbeing removed charge spout 12, which is formed of metal from the levelof the molten metal while at from plate stock and may be cast integrallythe same time replenishing with fresh slag, with the shell 10 orconnected thereto in any -or introducing any factor as a reagent orapproved manner.

scavenger to the slag, or air may be The spout tapers from the outerupper end in contact with the metal to hasten reduction 13 to the lowerinner end 14 so that the port of the carbon. 15 is of less diameter thanthe upper end of A further object of the invention is the prothe spout.The spout is provided with a parvision of an apparatus in the form of anopen tition 16 at the outer end'thereof which has a vessel partiallyfilled with a filtering'madischarge opening 17 disposed insubstanterial, such as molten slag, the open end being tially the samehorizontal plane as the. level partially closed with a perforated disk,19 of the molten metal 20 in the vessel. formed of fire resistantmaterial of ahighly The port 15 is at the outer end of a disrefractoryclay, this being provided with a: charge passage 21 formed through theinplurality of perforations, the bottom of the terior lining 11. Thedischarge opening vessel having an outlet in communication is locatedsufliciently above the bottom 22 of with the bottom of the vessel fordischargthe vessel that a certain quantity ofthe ing the molten metal ata point approximate molten metal 20 will be entrapped in the ly adjacentthe level of the molten metal, the lower end of the vessel. dischargeend being of a greater diameter The vessel is provided with apredeterthan the inlet end, with the discharge en d mined thickness ofmolten slag, which can be provided with a passage normally plugged,prepared in a separate furnace or cupola, if for removing lean slagwhich is exhausted volume is desired. but a small charge may be andwhich may be drained from the surface developed by melting glass in aseparate vesof the molten metal. sel. The slag is adapted to float uponthe top This invention will be best understood of the molten metal 20when sufiicient liquid "from a consideration of the following de metalhas been poured into the vessel to pro- 0 tailed description, inconnection with the acvide a level as indicated at 19.

companying drawings; nevertheless, it is to While the vessel is normallyopen at the 2 as er top, I provide a perforated disk 24 made of a highrefractory material which will stand the intense heat of the moltenmetal when poured from a spout 25. The member 24 consists of a diskhaving a plurality of perforations 2G of such cross sectional area aswill be suitable for the purpose. The portions of the disk, as shown at27, adjacent the periphery rest upon the upper end of the refractorylining 11 and a flange 28 at the periphery and rising above the outersurface of said disk will aid in preventing the molten metal fromsplashing over the sides of the perforated disk. The disk also acts tobreak the fall of the incoming stream of molten metal.

An opening 29' is for-med'at the lower end of the retort through therefractory lining l1 and also in the outer casing 10 to provide apassage for the removal of the molten metal from the vessel whenever itmay be desired. A plug 30 composed of clay isadapted to normallymaintain the passage closed to prevent the loss of metal during thecarrying out of the process.

Passages 40 for the introduction of oxygen or air under pressure, areprovided in the walls of the retort. The port slants through the lining11 and also the casing at an acute angle to deflect air over the surfaceof the molten metal, when so desired for reducing essential elements. 1

A passage 31 is formed in the lining 11 and also in the casing, 10 at apoint which is substantially in the same horizontal plane as the levelof the molten metal liquid 20, whereby the weak slag or contaminatedslags may be drained off at this point. A plug 32 of clay is adapted tomaintain the passage 31 normally closed.

An opening 34: is formed in the upper end of the wall 11 and the casing10 to permit the exhausted gases to escape and also acting as an inletfor the replenishing of essential compounds for aiding in building upthe slag or for bringing the compounds into contact with the metal bythe aid of the slag. This port may be closed by a brick when desired.

In carrying out my process the vessel 10 of my apparatus should beconveniently located in line with the pouring spout of a cupola orvessel used in pouring molten metal, or in line with the run spout of afurnace. The passages 29 and 31 are plugged as shown, prior to thepouring of the metal into the vessel. As the molten metal strikes thedisk member 29 it is broken into finely divided streams anddisintegrated in this manner before it enters the vessel and passes oninto the slag which rises to the top of the entrapped molten metal, (notshown).

As the molten metalreaches the level 19 a plug at the throat of thespout is forced back and the metal flows from the port 17. The pouringof the molten metal in its sprayed effect and disintegrated conditionthrough slag an the molten metal.

the slag causes the metal to pass out through the spout 12. Since themetal upon leaving the furnace or cupola has a temperature ofapproximately 2700 F. the metal heats the slag and maintains it at thesame temperature.

The treatment of the metal by the molten slag has a decided use intrapping oil the oxides, metalloids, and gases entrained in the metaldue to the fact that the molten slag has an affinity for these elementsand therefore the slag acts as a scavenger and a reagent in the fluxingof the metal. In this manner the slag is able to contain and retainelements essential to the quality of the metal. As the molten metal isin a sprayed and disinte grated condition it offers a wide range ofattack by the reducing gaseous effects of the compounds or minerals usedin connection with the slag, and since some of the compounds are highlyvolatile they can be retarded and retained by the blanket of slag. Otherreducing agents may be resorted to to act upon the metal in this sprayedand disintegated condition.

When necessary a batter of the vessels may be so connected that tie-molten metal passing through the first vessel will be dis chargedthrough the spout of the first vessel and into a second vessel toprovide acontinuous path whereby the molten metal may be acted upon bythe chemical condition of the its compounds.

It may be required to divide the volume of the molten metal leaving thespout of a cupola or furnace into a number of streams with each directedto a separate apparatus since the flow may be too great to handle as asingle stream.

During the melting down process of the metal the volatilized mineralgases and other elements which contaminate the metal and which areentrapped in the molten metal are acted upon by the reagents andcompounds in the molten slag or sinter which float upon It will be notedthat the filtering process functions continuously as the metalpercolates or passes through the slag and whereby the metal is washed bythe slag and cleansed of impurities by reason of the strong aflin-ity ofthe different slags for the gases. These impurities which contaminatethe molten metal if not reduced will injure subsequent castings.

The weak and exhausted contaminated slag is revived but when spent isundesirable and is removed from time to time from the level 19 of theliquid 20 through the passage 31 after the plug has been removed.

Other materials such as re-agents Or scavengers can be introducedthrough the opening 34 for thereplenishing of the slag during its nowpossible to revive or build up slags by the present method andapparatus. By tapering the spout 12 it will be seen that a betterbalance is had between the two columns of liquid, and the slag, andbetter access to the plug used in the throat of the pouring spout isprovided "for,

I claim l An apparatus-for the reduction of the elements from moltenmetals, which has been.

run directly from a melting unit comprising an open vessel formed of ametal shell, a refractory lining within the shell, said shell and liningbeing provided with an outlet pas-.

sage adjacent the lower end thereof, a discharge spout connected withthe passage and tapering from the outer free end thereof towards theinner end where it is'connected with the passage in the shell andlining, the outer free end of the spoutbeing provided with a dischargeport, the shell and lining port of the. spout.

having air inlet passages opening into the vessels at points above butadjacent a horizontal plane passing through the discharge LLEW LLYNJONES.

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